On Sat, 17 Aug 2024 17:36:47 +0300
Alexandru Ardelean <aardelean@xxxxxxxxxxxx> wrote:
> The ad7606_scan_direct() function returns 'int', which is fine for 16-bit
> samples.
> But when going to 18-bit samples, these need to be implemented as 32-bit
> (or int) type.
>
> In that case when getting samples (which can be negative), we'd get random
> error codes.
> So, the easiest thing is to just move the 'val' pointer to
> 'ad7606_scan_direct()'. This doesn't qualify as a fix, it's just a
> preparation for 18-bit ADCs (of the AD7606 family).
Send it at the start of that series then so as not to confuse me :)
>
> Signed-off-by: Alexandru Ardelean <aardelean@xxxxxxxxxxxx>
> ---
> drivers/iio/adc/ad7606.c | 8 ++++----
> 1 file changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/iio/adc/ad7606.c b/drivers/iio/adc/ad7606.c
> index dba1f28782e4..68481e97e50a 100644
> --- a/drivers/iio/adc/ad7606.c
> +++ b/drivers/iio/adc/ad7606.c
> @@ -138,7 +138,8 @@ static irqreturn_t ad7606_trigger_handler(int irq, void *p)
> return IRQ_HANDLED;
> }
>
> -static int ad7606_scan_direct(struct iio_dev *indio_dev, unsigned int ch)
> +static int ad7606_scan_direct(struct iio_dev *indio_dev, unsigned int ch,
> + int *val)
> {
> struct ad7606_state *st = iio_priv(indio_dev);
> int ret;
> @@ -153,7 +154,7 @@ static int ad7606_scan_direct(struct iio_dev *indio_dev, unsigned int ch)
>
> ret = ad7606_read_samples(st);
> if (ret == 0)
> - ret = st->data[ch];
> + *val = (short)st->data[ch];
I'd rather see a sign_extend32() for that seeing as you are touching the code.
obviously it's the same thing but nicer to read!
>
> error_ret:
> gpiod_set_value(st->gpio_convst, 0);
> @@ -173,10 +174,9 @@ static int ad7606_read_raw(struct iio_dev *indio_dev,
> switch (m) {
> case IIO_CHAN_INFO_RAW:
> iio_device_claim_direct_scoped(return -EBUSY, indio_dev) {
> - ret = ad7606_scan_direct(indio_dev, chan->address);
> + ret = ad7606_scan_direct(indio_dev, chan->address, val);
> if (ret < 0)
> return ret;
> - *val = (short) ret;
> return IIO_VAL_INT;
> }
> unreachable();
